/**
 * Copyright (c) 2011-2023, James Zhan 詹波 (jfinal@126.com).
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.jfinal.template.stat.ast;

import com.jfinal.template.Env;
import com.jfinal.template.TemplateException;
import com.jfinal.template.expr.ast.Expr;
import com.jfinal.template.expr.ast.ExprList;
import com.jfinal.template.io.Writer;
import com.jfinal.template.stat.Location;
import com.jfinal.template.stat.ParseException;
import com.jfinal.template.stat.Scope;

/**
 * Output 输出指令
 * 
 * 用法：
 * 1：#(value)
 * 2：#(x = 1, y = 2, x + y)
 * 3：#(seoTitle ?? 'JFinal 极速开发社区')
 */
public class Output extends Stat {

    protected Expr expr;

    public Output(ExprList exprList, Location location) {
        if (exprList.length() == 0) {
            throw new ParseException("The expression of output directive like #(expression) can not be blank", location);
        }
        this.expr = exprList.getActualExpr();
    }

    public void exec(Env env, Scope scope, Writer writer) {
        try {
            Object value = expr.eval(scope);

            if (value instanceof String) {
                String str = (String)value;
                writer.write(str, 0, str.length());
            } else if (value instanceof Number) {
                Class<?> c = value.getClass();
                if (c == Integer.class) {
                    writer.write((Integer)value);
                } else if (c == Long.class) {
                    writer.write((Long)value);
                } else if (c == Double.class) {
                    writer.write((Double)value);
                } else if (c == Float.class) {
                    writer.write((Float)value);
                } else {
                    writer.write(value.toString());
                }
            } else if (value != null) {
                writer.write(value.toString());
            }
        } catch (TemplateException | ParseException e) {
            throw e;
        } catch (Exception e) {
            throw new TemplateException(e.getMessage(), location, e);
        }
    }
}




